Area Of a Trapizium

#include<stdio.h>
int main()
{
    float a,b,d,area;
    printf("Enter the value of a==");
    scanf("%f",&a);
    printf("enter the value of b==" );
    scanf("%f",&b);
    printf("enter the value  of d==");
    scanf("%f",&d);
    area=(0.5*(a+b)*d);
    printf("The t is %0.4f",area);
    return 0;
}